irqchip/gic/realview: Fix refcount leak in realview_gic_of_init

irqchip/gic/realview: Fix refcount leak in realview_gic_of_init

This is an automated ID intended to aid in discovery of potential security vulnerabilities. The actual impact and attack plausibility have not yet been proven.
This ID is fixed in Linux Kernel version v4.9.320 by commit 87da903ce632d5689bef66d56ee5dae700d82104, it was introduced in version v4.6 by commit 82b0a434b436f5da69ddd24bd6a6fa5dc4484310. For more details please see the references link.